There is significant interest in synthesizing large-area graphene films at low temperatures by chemical vapor deposition (CVD) for nanoelectronic and flexible device applications. However, to date, low-temperature CVD methods have suffered from lower surface coverage because micro-sized graphene flakes are produced. Here, we demonstrate a modified CVD technique for the production of large-area, continuous monolayer graphene films from benzene on Cu at 100–300 °C at ambient pressure. In this method, we extended the graphene growth step in the absence of residual oxidizing species by introducing pumping and purging cycles prior to growth. This led to continuous monolayer graphene films with full surface coverage and excellent quality, which were comparable to those achieved with high-temperature CVD; for example, the surface coverage, transmittance, and carrier mobilities of the graphene grown at 300 °C were 100%, 97.6%, and 1,900–2,500 cm2 V−1 s−1, respectively. In addition, the growth temperature was substantially reduced to as low as 100 °C, which is the lowest temperature reported to date for pristine graphene produced by CVD. Our modified CVD method is expected to allow the direct growth of graphene in device manufacturing processes for practical applications while keeping underlying devices intact.

The lateral flow immunosensor (LFI) is a widely used diagnostic tool for biomarker detection; however, its sensitivity is often insufficient for analyzing targets at low concentrations. Here, an electrochemiluminescent LFI (ECL‐LFI) is developed for highly sensitive detection of troponin I (TnI) using Ru(bpy)32+‐loaded mesoporous silica nanoparticles (RMSNs). A large amount of Ru(bpy)32+ is successfully loaded into the mesoporous silica nanoparticles with excellent loading capacity and shows strong ECL signals in reaction to tripropylamine. Antibody‐immobilized RMSNs are applied to detect TnI by fluorescence and ECL analysis after a sandwich immunoassay on the ECL‐LFI strip. The ECL‐LFI enables the highly sensitive detection of TnI‐spiked human serum within 20 min at femtomolar levels (≈0.81 pg mL−1) and with a wide dynamic range (0.001–100 ng mL−1), significantly outperforming conventional fluorescence detection (>3 orders of magnitude). Furthermore, TnI concentrations in 35 clinical serum samples across a low range (0.01–48.31 ng mL−1) are successfully quantified with an excellent linear correlation (R2 = 0.9915) using a clinical immunoassay analyzer. These results demonstrate the efficacy of this system as a high‐performance sensing strategy capable of capitalizing on future point‐of‐care testing markets for biomolecule detection.

A lithographically aligned palladium nano-ribbon (Pd-NRB) array with gaps of less than 40 nm is fabricated on a poly(ethylene terephthalate) substrate using the direct metal transfer method. The 200 μm Pd-NRB hydrogen gas sensor exhibits an unprecedented sensitivity of 10(9) % after bending treatment, along with fast sensing behavior (80% response time of 3.6 s and 80% recovery time of 8.7 s) at room temperature.

The production of hydrogen peroxide (H2O2) using photocatalytic nanoparticles is an emerging field with applications in organic synthesis, biosensors, and fuel cells. Colloidal photocatalysts are, however, limited in their applications because of poor efficiency and stability. In this study, millimolar production of H2O2 was achieved within 5 min using solid-phase photocatalystsAu nanoislands (NIs) on porous TiO2 filmswithout supplying O2 or stirring the solution. Au/TiO2 showed an almost 80-fold greater productivity than TiO2, which can be explained by considering two factors. First, the physical-vapor-deposited Au resulted in the formation of Au NIs of various sizes on TiO2, whose work functions were size-dependent. Thus, the combination of small Au NIs, TiO2, and large Au NIs allowed the introduction of potential gradients through TiO2, and also the reduced potential barriers at the small Au NI/TiO2 junctions; thereby minimizing the recombination of electron–hole pairs, and effectively extracting them. Second, the porous TiO2 films may effectively scatter UV light, leading to enhanced electron–hole pair generation. The inherent properties of the solid-phase photocatalysts could also circumvent stability issues caused by aggregation. These solid-phase photocatalysts should facilitate the development of high-efficiency H2O2 generation and promote technology based on H2O2-mediated processes.

To date, the fabrication of highly uniform large‐scale monolayer and few‐layer p‐type WSe2 throughout the entire substrate, especially on SiO2/Si substrates is significantly challenging and one of the most important issues. Here, the fabrication of highly uniform monolayer and few‐layer WSe2 thin films on a centimeter‐scale SiO2/Si substrate via pulsed laser deposition is reported. The number of WSe2 layers and the thickness, controlled by varying the number of laser pulses, is determined by transmission electron microscopy analysis. The high uniformity of the as‐grown WSe2 thin film on the entire SiO2/Si substrate is verified by the uniform Raman peak position and intensity, estimated by Raman mapping. Using a conventional photolithography process, field effect transistors based on the as‐grown WSe2 thin films are fabricated and their electrical characteristic is analyzed.

C-reactive protein (CRP) is used as a general biomarker for inflammation and infection. During stroke and myocardial infarction, CRP increases and is present in a broad concentration range of 1−500 μg/mL. Therefore, full-range CRP detection is crucial to identify patients who need close follow-up or intensive treatment after a heart attack. Here, we report the first attempt to develop an electrochemiluminescent lateral flow immunosensor (ECL-LFI) that allows full-range CRP detection. Ru(bpy) 3 2+ -labeled gold nanoparticles (AuNPs) are used as a CRPtargeting probe and a signal generator; they form sandwich immunocomplexes at the test line of the strip and generate strong ECL emission via a Ru(bpy) 3 2+ /tripropylamine system. The ECL-LFI shows high sensitivity in detecting CRP in spiked serum, with a limit of detection of 4.6 pg/mL within 15 min, and a broad detection range of 0.01−1000 ng/mL, which is 2 orders of magnitude broader than that of conventional colorimetric LFI. The clinical usability of the ECL-LFI was evaluated using 30 clinical serum samples (200 ng/mL to 5 mg/mL), which showed a good linear correlation (R 2 = 0.9896), with a clinical chemistry analyzer. The results suggest that the ECL-LFI holds great potential for CRP detection in point-of-care diagnostics.

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While quinoidal moieties are considered as emerging platforms showing efficient charge transport and interesting open-shell diradical characteristics, whether these properties could be changed by extension to the conjugated polymer structure remains as a fundamental question. Here, we developed and characterized two conjugated polymers incorporating quinoids with different lengths, which have a stable close-and open-shell diradical character, respectively, namely, poly(quinoidal thiophenethienylene vinylene) (PQuT-TV) and poly(quinoidal bithiophene-thienylene vinylene) (PQuBT-TV). A longer length of a quinoidal core led to enhanced diradical characteristics. Therefore, the longer core length of QuBT was favorable for the formation of an open-shell diradical structure in its monomer and in the quinoidal polymer. PQuBT-TV exhibited high spin characteristics observed by the strong ESR signal, a low band gap, and improved electrochemical stability. On the other hand, as QuT maintained a closed-shell quinoid structure, PQuT-TV exhibited high backbone coplanarity and strong intermolecular interaction, which was beneficial for charge transport and led to high hole mobility (up to 2.40 cm 2 V −1 s −1 ) in organic field-effect transistors. This work successfully demonstrated how the control of the closed/open-shell character of quinoidal building blocks changes charge transport and spin properties of quinoidal conjugated polymers via quinoid−aromatic interconversion.